Textile apron stabilizing and cleaning system for drafting units



Oct. 17, 1967 E. ANDREANI 3,346,926

TEXTILE APRON STABILIZING AND CLEANING SYSTEM FOR DRAFTING UNITS 2 Sheets-Sheet 1 Filed Jan. 5, 1966 Z6 INVENTORI Z4 EUGENIOANBEE-ANI ATTORNEYS ct. 17, 39%? E. ANDREANI 3,346,926

TEXTILE APRON STABILIZING AND CLEANING SYSTEM FOR DRAFTING UNITS Filed Jan. 5, 1966 2 Sheets-Sheet 2 INVENTOR: Euqewo ANbRE-ANI ATTORNEYS United States Patent 3,346,926 TEXTILE APRON STABILIZING AND CLEANING SYSTEM FOR DRAFTING UNITS Eugenio Andreani, Bergamo, Italy Filed Jan. 5, 1966, Ser. No. 518,863 Claims priority, applicatgon Italy, Jan. 5, 1965, 0/

9 Claims. (Cl. 19-245) ABSTRACT OF THE DISCLOSURE This invention relates to apron type drafting systems, and more especially, to improved apparatus for stabilizing drafting aprons or belts with respect to rolls on which they are mounted, including novel means for maintaining the inner surfaces of the aprons or belts free of lint, dust and other foreign matter to further insure proper tracking of the aprons or belts.

It is well known that, in apron type drafting systems, upper and lower endless flat belts or aprons are employed with their proximal runs in contact with each other and, generally, the lower belt is driven and the upper belt is driven by frictional contact with the lower belt and with the textile material or fibers passing therebetween. With the pair of belts thus arranged there is formed between them a zone for distributing, straightening and parallelizing the fibers.

While such superposed aprons or belts contribute to control of the fibers during drafting, reduce breaking of the fibers and make it possible to draft textile fibers of any species, nature and length, depending upon the location of related drafting rolls with respect to the aprons, prior art apron drafting systems have had the drawback of the tendency toward sideslip of the belts relative to each other and, also, the formation on both the driving and driven rolls, which support the belts, of uneven wads or layers of lint fibrils, dust or other foreign matter which deform the perfect flatness of the belts in the zone of contact of the belts, with a consequent loss of perfect parallelizing and controlling of the fibers.

It is therefore an object of this invention to provide a double apron drafting system of the character described in which the belts and their supporting rollers are specially constructed to prevent sideslipping of the belts relative to each other and wherein means are provided for continuously directing air into the loops formed of the respective belts and against the inner surfaces of the belts and the rolls about which they are entrained to prevent lint and other foreign matter from collecting on the rolls or the belts, thus further insuring that the belts will not sideslip and also insuring that the proximal runs or reaches of the belts are maintained substantially parallel at all times and that any deformation of the proximal runs of the belts will only be the result of the fibers to be drafted passing therebetween.

Some of the objects of the invention having been stated, other objects will appear as the description proceeds when taken in connection with the accompanying drawings in which- FIGURE 1 is an exploded perspective view of the upper and lower belts with parts broken away and showing the improved pneumatic cleaning means in association therewith;

FIGURE 2 is a longitudinal vertical sectional view through a double apron drafting system incorporating the features of the instant invention;

FIGURE 3 is an enlarged fragmentary vertical sectional view taken longitudinally of corresponding rolls of the drafting unit and substantially along line 33 in FIGURE 2;

FIGURE 4 is an enlarged fragmentary View of the central portion of one of the blowing cleaning devices of the present invention; and

FIGURE 5 is an exploded perspective view of the structure shown in FIGURE 4.

Referring more specifically to the drawings, the numerals 10 and 11 indicate top and bottom feed rolls of the drafting unit which feed slivers or other textile fibers S between the proximal runs of upper and lower endless drafting aprons or belts 12, 13, from whence the slivers are drafted through a pair of top and bottom delivery drafting rolls 14, 15. As is usual, bottom drafting rolls 11, 15 are driven by conventional means, not shown but well known in the art, with roll 15 being driven at a faster surface speed than roll 11. An apron-supporting bottom roller 16 is also driven by such conventional means at a predetermined speed relative to that of drafting rolls 11, 15. Apron driving roller 16, along with a tensioning roller 17, a nose bar or roller 20, and an intermediate slip roller 21 between rollers 16, 21), have the endless lower apron 13 mounted thereon. A second tension roller 22 engages the outer surface of apron 13 at a point spaced substantially below the level of drafting rolls 11, 15.

Tension rollers 17, 22 are journaled on common blocks 24, only one of which is shown and which are interconnected by a rigid bar 26. Blocks 24 are journaled on the V frame 27 of the drafting unit and are locked in adjusted position, so as to maintain belt or apron 13 under proper tension, by a lock nut 30. The specific construction and manner of operation of the tension rollers 17, 22 may be such as is shown in the copending application of Gianfranco Andreani, Ser. No. 385,689, filed July 28, 1964, and entitled, Double Apron Drafting System for Drawing Frames, to which reference is made for a more detailed disclosure of the type drafting system described herein. Rolls 10, 11, 14, 15, 16, 20, 21 are supported in corresponding roll stands generally designated at 31 and carried by the frame 27 of the textile machine.

Upper endless belt or drafting apron 12 is carried by a top cradle broadly designated at 35 and comprising a pair of end plates or blocks 36, 36, each of which preferably is shaped substantially according to the contour of the outer surface of top apron 12. End blocks 36, 36' are spaced apart a distance substantially equal to or slightly greater than the width of top apron 12. Rear and front portions of upper or top apron 12 are supported by respective rear and front top-apron-supporting rollers 37, 38 disposed above the respective botton-apronsupporting rollers 16, 20 so as to form a bottom run of the top apron 12 extending substantially parallel with and in close proximity to or in engagement with the top run of bottom apron 13. Reduced opposite ends of rear top-apron-supporting roller 37 loosely penetrate the rear portions of the end blocks 36, 36 of cradle 35 and have respective elongate bearings 42, 42' mounted thereon, which bearings may be suitably attached to the distal surfaces of end blocks 36, 36'. The distal ends of bearings 42, 42' have respective reduced portions or axial projections thereon which loosely fit in suitable grooves 44 formed in corresponding bearing blocks 31. Thus, cradle 35 is, in effect, pivotally mounted on roller 37. Reduced opposite ends of front-apron-supporting roller 38 may be journaled in end blocks 36, 36.

As best shown in FIGURES 1 and 2, the upper portion of top apron 12 is entrained over a tensioning roller-'15 whose opposed ends may be journaled on stub shafts 46. Reduced outer ends of the stub shafts 46 are vertically adjustable in slots 47, only one of which is shown in FIG URE 2, formed in the proximal portions of end blocks 36, 36. The reduced outer end portions of stub shafts 46 may be secured in adjusted position by suitable screws 50 which loosely penetrate the upper portions of the blocks 36, 36' and may be threaded through the reduced portions of the corresponding stub shafts 46 on which tensioning roller 45 is journaled. A top slip roll 52 may be provided for cooperation with the bottom slip roll 21 and the proximal runs of belts 12, 13 passing therebetween. Reduced opposed ends of top slip roll 52 loosely penetrate corresponding slots 53 in end blocks 36, 36, and are journaled in suitable bearings 54 which may be mounted inthe same manner as bearings 42, 42.

In order to prevent aprons 12,. 13 from sliding sideways relative to each other and relative to the rollers on which they are mounted, the belts, which are made from a pliable plastic material, rubber or the like, have respective pairs of inwardly projecting broad flat strips or ribs 60, 61 formed integral therewith and projecting inwardly from the inner surfaces thereof and which engage corre sponding steps or annular grooves 62, 63 formed in the peripheries of the respective sets of rollers 37, 38, 45, 52 and 16, 17, 20, 21, about which the respective aprons 12, 13 are entrained. It will be noted in FIGURE 3 that the annular grooves 62, 63 are of a shape similar to the projecting strips 60, 61 of the belts or aprons 12, 13 so as to constitute housings for said strips and therefore to maintain the belts in proper position during their travel while thus eliminating any sideslip of thebelts. The ribs or strips 60, 61 are spaced inwardly a short distance from the corresponding distal edges of the belts 12, 13 so that the side walls of the grooves 62, 63 formed in corresponding rollers engage both side walls of the corresponding ribs 60, 61.

To further assist in insuring elimination of sideslip of the belts, by preventing accumulation of lint and other foreign matter between the ridges 60, 61 and the grooves 62, 63 in the corresponding beltsupporting rollers, and to also prevent accumulations of lint and other foreign matter from passing between the belts and the cone sponding rollers in such a manner as to deform the perfect flatness of the belts at the proximal runs thereof, air-blowing cleaning devices broadly designated at 65, 65' are positioned within the loops formed of the respective top and bottom aprons or belts 12, 13 and are arranged at a point most suitable for distributing the air in the form of several jets by continuous blowing through the spaces of the shoulders and edges of the flat belts to effectively blow lint and other light foreign matter outwardly and away from the interior portions of the belts as well as the adjacent portions of the drafting unit.

The blowing-air cleaning devices 65, 65 comprise respective composite shafts or elongate bars formed of two axially aligned sections 66, 67 and 66, 67', respectively, and which are suitably interconnected in the form of respective enlarged portions 70,. 70 at their proximal portions and about midway of the width of the corresponding belts 12, 13. The enlarged portion 70 of the upper air-blowing cleaning device 65 is shown in FIG- URES 4 and in detail, it being understood that the enlarged portion 70' of the bottom blowing-air cleaning device 65 may be constructed in a similar manner. In FIGURES 4 and 5, it will be observed that the enlarged portion 70 of cleaning device 65 is formed with an annular cavity or chamber 72 therein through which a reduced portion of shaft section 66 extends to be received in a correspondingly shaped cavity 73 formed in the corresponding end of shaft section 67. The shaft section 66 has an elongate longitudinally extending air passageway 75 therein which communicates, with the annular cavity or chamber 72 in enlarged portion 70. The elongate passageway in shaft section 66, corresponding to passageway 75 in shaft section 66, is indicated at 75.

As shown in FIGURES 1 and 3, the axially aligned and interconnected shaft sections 66, 67 of cleaning device 66 penetrate. the end blocks 36', 36, respectively, and made be secured thereto by means of corresponding nuts 77, 78 threaded onto the respective shaft sections 66, 67. In addition to serving as parts of cleaning device 65, shaft sections 66, 67 also serve as pressure receiving members for transmitting downward pressure from respective weighting devices or yieldable pressure devices 81, 82 to the end blocks 36, 36' of cradle 36 and, thus, to the top-apron-supporting rollers 37, 38 to maintain the bottom run of top apron 12 in pressure engagement with the top run of bottom apron 13 or with the textile material passing therebetween. Weighting devices similar to devices 81, 82 also may be provided for engaging the bearings 54 in which reduced opposite ends of top slip roll 52 are journaled to apply downward pressure to slip roll 52 toward the bottom slip roll 21. The axially aligned and interconnected shaft sections 66', 67 of the bottom aireblowing cleaning device 65 may besecurecl to suitable brackets 85 carried by and projecting inwardly from corresponding bearing blocks or roll stands 31.

As shown in FIGURES 3, 4 and 5, opposed ends of each enlarged medial portion 70, 70 of the air cleaning devices 65, 65 have outwardly directed jet. openings 86,

87 formed therein which direct jets of air outwardly from the corresponding chamber 72 toward the central portions of the belts adjacent their proximal runs and toward the outer edge portions of the belts so thejets of air from top cleaning device 65 pass between the edges of the upper belt 12 and the end blocks 36,36, and so the jets of air from the bottom air cleaning device 65', pass outwardly of opposite ends of lower belt 13 while impinging against the inner surfaces of the belts, and particularly against the inner surfaces of the proximal runs of the belts 12, 13. In order to introduce'air into the central chamber 72 of each cleaning device 65, 65., the outer ends or end portions of the tubular shaft sections 66, 66 of the respective cleaning devices 65, 65' have corresponding ends, of respective compressed air lines or pipes 90, 90', communicatively connected there to. The other ends of pipes 90, '90 may be connected to any suitable source of compressed air shown schematically at 91 in FIGURE 3.

It is thus seen that the air is distributed at various points around the interior surfaces of the flat belts in the form of several radial jets. It is to be understood that the rollers which support the belts may be constructed substantially in the manner of the devices 65, 65, but without being enlarged at their central portions, so as to effect radial flow of compressed air into the spaces defined by the respective belts 12, 13, without departing from the spirit of the invention.

It is to be noted that the thickness of the ribs 60, 61 and the depth .of corresponding annular grooves 62, 63 are such that substantially the remainder of the inner surface of each belt 12, 13 is in contacting engagement with the peripheral surfaces of the corresponding supporting rollers as it moves therearound, thus insuring that the working surfaces of the belts are adequately supported to keep them flat and to maintain traction between the belts and the supporting rollers.

It is also apparent that the cleaning devices 65, 65' constitute pneumatic means associated with the respective belts 12, 13 for preventing foreign matter, such as lint and the like, from collecting inside the apron and interfering with the mating relationship of the ribs on the belts with the grooves in the corresponding supporting rolls. Further, it will be noted that the end blocks 36, 36 straddle the top or upper belt 12 in such a manner as to form a small space between the edges of the top belt 12 and the blocks 36, 36' through which the air directed against the inner surfaces of the aprons and the ribs by the upper air-blowing cleaning device 65 is exhausted to further assist in keeping the outer surfaces of the upper belt and adjacent parts of the drafting unit free of lint and other light foreign matter.

In the drawings and specification there has been set forth a preferred embodiment of the invention and, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being defined in the claims.

Iclaim:

1. In a textile drafting apparatus having an endless belt drafting apron and a plurality of spaced apart supporting rollers about which the belt is looped for movement therearound, the improvement comprising at least two spaced apart parallel endless ribs formed integral with and projecting inwardly from said apron along its inner surface and said ribs being spaced inwardly from opposite side edges of the apron, said supporting rollers each having annular peripheral grooves therein spaced inwardly of opposite ends of the rollers and being of substantially the same size and configuration as said ribs and mating therewith to prevent sideslipping of the apron relative to the supporting rollers, substantially the remainder of the inner surface of the belt being in contacting engagement with the peripheral surfaces of the supporting rollers as it moves therearound, and pneumatic means associated with said apron and including air directing means positioned near the interior medial portion of the apron for directing air in opposing directions generally toward the opposite side edges of the apron for preventing foreign matter, such as lint and the like, from collecting inside the apron and interfering with the mating relationship of the ribs with the grooves in the supporting rollers.

2. Apparatus according to claim 1, in which said air directing means includes means for directing the air in the form of a plurality of jets.

3. Apparatus according to claim 1, in which said air directing means comprises an elongate bar having an enlarged portion adjacent the central interior portion of the belt, said enlarged portion having a plurality of jet openings therein for directing air generally toward the inner surface of the belt and its opposite side edges, and communicative means in said bar connecting said jet openings with a source of compressed air.

4. Apparatus according to claim 1, including end blocks straddling said belt and supporting said rollers, there being a small space between the edges of the belt and the blocks through which the air directed against the inner surfaces of the apron and the ribs is exhausted.

5. Apparatus according to claim 4, in which said air directing means includes an elongate rigid member eX- tending between and supported by said end blocks and having a plurality of radial jet openings therein for di recting air generally toward the inner surface of the belt and said end blocks, and communicative means in said elongate rigid member for connecting said jet openings with a source of compressed air.

6. Apparatus according to claim 5, in which said drafting apparatus includes a second endless belt drafting apron cooperating with and supported beneath said firs-tnamed apron, said rigid member being extended through said blocks and projecting outwardly thereof, and means for applying downward pressure to said first-named apron, including a pair of spaced apart pressure-applying devices engaging said rigid member outwardly of said blocks.

7. In a textile drafting apparatus having at least one endless belt drafting apron and a plurality of spaced apart supporting rollers about which said apron is looped for movement therearound, means positioned within the loop formed by said apron for directing air against the inner surface of the apron to aid in maintaining said inner surface free of lint and the like, said means comprising an elongate rigid member having a plurality of radial jet openings therein near the medial interior portion of the apron for directing air generally toward the opposite side edges of the apron, and said rigid member having communicative means therein for connecting said ijet openings with a source of compressed air.

8. Apparatus according to claim 7, including end blocks straddling said apron and supporting said rollers and said rigid member, and there being a small space between the side edges of the apron and said blocks through which the air being directed against the inner surface of the apron is exhausted.

9. Apparatus according to claim 8, in which said draft ing apparatus includes a second endless belt drafting apron cooperating with and supported beneath said firstnamed apron, said rigid member extending through said blocks and projecting outwardly of said blocks, and means for applying downward pressure to said first-named apron including a pair of spaced apart pressure-applying devices engaging said rigid member outwardly of said blocks.

References Cited UNITED STATES PATENTS 207,626 9/1878 Sargent 74229 1,235,027 7/1917 Harrison 198230 2,074,556 3/ 1937 Pilz 19--245 FOREIGN PATENTS 945,436 12/ 1963 Great Britain.

604,294 3/ 1960 Italy.

MERVIN STEIN, Primary Examiner. I. C. WADDEY, Assistant Examiner. 

1. IN A TEXTILE DRAFTING APPARATUS HAVING AN ENDLESS BELT DRAFTING APRON AND A PLURALITY OF SPACED APART SUPPORTING ROLLERS ABOUT WHICH THE BELT IS LOOPED FOR MOVEMENT THEREAROUND, THE IMPROVEMENT COMPRISING AT LEAST TWO SPACED APART PARALLEL ENDLESS RIBS FORMED INTEGRAL WITH AND PROJECTING INWARDLY FROM SAID APRON ALONG ITS INNER SURFACE AND SAID RIBS BEING SPACED INWARDLY FROM OPPOSITE SIDE EDGES OF THE APRON, SAID SUPPORTING ROLLERS EACH HAVING ANNULAR PERIPHERAL GROOVES THEREIN SPACED INWARDLY OF OPPOSITE ENDS OF THE ROLLERS AND BEING OF SUBSTANTIALLY THE SAME SIZE AND A CONFIGURATION AS SAID RIBS AND MATING THEREWITH TO PREVENT SIDELIPPING TO THE APRON RELATIVE TO THE SUPPORTING ROLLERS, SUBSTANTIALLY THE REMAINDER OF THE INNER SURFACE OF THE BELT BEING IN CONTACTING ENGAGEMENT WITH THE PERIPHERA SURFACES OF THE SUPPORTING ROLLERS AS IT MOVES THEREAROUND, AND PNEUMATIC MEANS ASSOCIATED WITH SAID APRON AND INCLUDING AIR DIRECTING MEANS POSITIONED NEAR THE INTERIOR MEDIAL PORTION OF THE APRON FOR DIRECTING AIR IN OPPOSING DIRECTIONS GENERALLY TOWARD THE OPPOSITE SIDE EDGES OF THE APRON FROM PREVENTING FOREIGN MATTER, SUCH AS LINT AND THE LIKE, FROM COLLECTING INSIDE THE APRON AND INTERFERING WITH THE MATING RELATIONSHIP OF THE RIBS WITH THE GROOVES IN THE SUPPORTING ROLLERS. 